Minimum XOR Sum of Two Arrays
A hard-tier problem at 49% community acceptance, tagged with Array, Dynamic Programming, Bit Manipulation. Reported in interviews at Media.net and 0 others.
Minimum XOR Sum of Two Arrays is a hard DP problem that shows up in Media.net interviews and is passed by just under half of candidates who attempt it. You're given two arrays and need to pair elements to minimize the total XOR of all pairs. It looks like a greedy problem at first, which is why candidates blank on it live. The trick is that locally optimal choices lead you into a corner. This is where StealthCoder steps in: if you hit this during your assessment and freeze, it surfaces the bitmask DP solution in seconds, keeping your momentum alive.
Companies that ask "Minimum XOR Sum of Two Arrays"
Minimum XOR Sum of Two Arrays is the kind of problem that decides whether you pass. StealthCoder reads the problem on screen and surfaces a working solution in under 2 seconds. Invisible to screen share. The proctor sees nothing. Built by an engineer who got tired of watching his cohort grind for six months and still get filtered at the OA stage.
Get StealthCoderThe naive approach is to sort and pair smallest with smallest, but XOR doesn't reward monotonic ordering the way sum does. The real pattern is a bitmask DP where you track which elements from the second array have been used, then recurse through the first array, trying each available pairing. The state space is manageable because array sizes are small enough that bitmask DP stays polynomial. Most candidates who struggle spend too long chasing greedy or two-pointer ideas before realizing you need state tracking. The bit manipulation topic is a red herring; the XOR itself is simple math. What kills you is not seeing that you need DP with a bitmask to represent which second-array elements remain. StealthCoder handles the state transitions and memoization so you can move on.
Pattern tags
You know the problem.
Make sure you actually pass it.
Minimum XOR Sum of Two Arrays recycles across companies for a reason. It's hard-tier, and most candidates blank under the timer. StealthCoder is the hedge: an AI overlay invisible during screen share. It reads the problem and surfaces a working solution in under 2 seconds. Built by an engineer who got tired of watching his cohort grind for six months and still get filtered at the OA stage. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Minimum XOR Sum of Two Arrays interview FAQ
Is this really a bitmask DP problem or can you solve it greedily?+
Greedy fails. Sorting either array or pairing smallest-to-smallest leads to suboptimal solutions because XOR has no monotonic property. You must explore multiple pairings, which requires DP with a bitmask to track which second-array elements are used. Acceptance rate near 50% reflects this trap.
How big can the arrays be for bitmask DP to work?+
Bitmask DP scales to roughly 20-24 elements because the state space is O(n * 2^n). The problem constraints typically keep array sizes small enough for this approach. Check the limits in your actual assessment, but if it's a hard DP problem, bitmask is the intended path.
Does understanding Bit Manipulation help solve this faster?+
Bit Manipulation is listed as a topic, but XOR itself is trivial. The real skill is recognizing that you need DP with state compression via bitmask. Bit manipulation fluency doesn't unlock the solution; DP architecture does.
Why isn't this problem asked more often if it's hard?+
Media.net is the only reported company in the data, suggesting niche appeal. Hard DP problems are filtered heavily during prep and aren't as common in typical FAANG loops as medium-difficulty DP. But if it's in your pipeline, you need to know it.
What's the time complexity I should target?+
Bitmask DP with memoization runs in O(n * 2^n * n) time roughly, where n is the array size. Space is O(n * 2^n) for the DP table. It's not pretty, but it's the correct approach and beats any greedy or brute-force attempt.
Want the actual problem statement? View "Minimum XOR Sum of Two Arrays" on LeetCode →